Abstract
The effects of histamine have been examined in anaesthetized cats and on cat isolated lung parenchyma strip. Histamine infused intravenously for 2 min produced a small and inconsistent effect on central airways and a small but consistent constriction of peripheral airways. Histamine bronchoconstriction of the central airways was unmasked by non‐selective and β2‐adrenoceptor blockade but not by β1‐adrenoceptor blockade. This bronchoconstriction was antagonized by atropine but not by cimetidine or prazosin. Bronchoconstriction of the peripheral airways was not affected in a dose‐related manner by β‐adrenoceptor blockade. The bronchoconstriction was antagonized by mepyramine but not by atropine or prazosin. β‐Adrenoceptor antagonists produced a bell‐shaped dose‐response curve on histamine contractions in cat isolated lung parenchyma strip. Strips of lung parenchyma obtained from reserpine‐treated cats produced a larger contraction to histamine which was not potentiated by propranolol. It is concluded that in the central airways, histamine bronchoconstriction produced by an action on irritant receptors is masked by an action on β2‐adrenoceptors of catecholamines released locally and from the adrenal glands. In the peripheral airways, histamine bronchoconstriction is mediated by H1‐receptors and bT2‐adrenoceptor blockade may either potentiate or antagonize the histamine response depending on the concentration. 1985 British Pharmacological Society
Original language | English (US) |
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Pages (from-to) | 309-316 |
Number of pages | 8 |
Journal | British Journal of Pharmacology |
Volume | 84 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1985 |
Externally published | Yes |
ASJC Scopus subject areas
- Pharmacology